1st January - Happy New Year.
14th February - Valentine Hearts.
1st April - April Fool, play as Reala (this will only work if you complete the normal game as NiGHTS).
31st October - Holloween.
31st December 2099 - Fluorescent Snow.
12:00am - Hearts
9:00am - Crescent Moons
12:00pm - Purple Confetti
3:00pm - Sweeties!
6:00pm - Weired Stars
(NOTE, you can put the Christmas Nights CD into your PC CD-ROM Drive, where you can access some hidden images)